Well, two things here. First, it could be a firewall problem because both errors show that our cluster manager is not able to connect to processes its normally spawning (so a firewall could prevent access).
The other thing as pointed out is that 4.6 does not support Windows Server 2016, but our April Developer build of Server 5.0 does - see https://blog.couchbase.com/couchbase-5-0-april-2017-developer-build/.